Joseph Netzer, a German immigrant, was an entrepreneur of the U.S.-Mexico borderlands. Along with many others, he journeyed to the US-Mexico border region in the late nineteenth century, attracted by new economic opportunities created by the construction of railroads that connected the industrializing areas of the U.S. with emerging capitalist centers in Mexico, including Monterrey and San Luis Potosi. Netzer, a hardware store owner and plumber by training, rose fairly rapidly to prominence in Laredo business and social circles. He became part of a cosmopolitan business class consisting of ethnic Mexicans, immigrants from western, southern and eastern Europe, from the Ottoman Empire, and from the northeastern and midwestern United States. His life illuminates the role of entrepreneurs who helped to integrate the U.S. and Mexican economies in that era.